A dead-end filtration set-up with a vertically vibrated medium is used to study cake permeation. A key feature of these experiments is that a sudden increase in permeability at a certain critical vibration amplitude takes place, when the static loading is light. A theory to explain this phenomenon is put forward in terms of a relation to local fluidization near the medium, thus returning the clogged septum resistance to virtually its unclogged value. The fluidization is due to a particle stress induced by the vibration of the particle fluid mixture near the medium. This stress can be large enough to counteract the compressive stress that is caused by gravity and drag due to the fluid flow in the set-up.